chore: retire preview markdown dialog

web/src/components/MemoEditor/ActionButton/MarkdownMenu.tsx

 import { Dropdown, IconButton, Menu, MenuButton, MenuItem } from "@mui/joy";
 import { Link } from "@mui/joy";
-import toast from "react-hot-toast";
 import Icon from "@/components/Icon";
-import showPreviewMarkdownDialog from "@/components/PreviewMarkdownDialog";
 import { EditorRefActions } from "../Editor";
 
 interface Props {
@@ -59,16 +57,6 @@ const MarkdownMenu = (props: Props) => {
     });
   };
 
-  const handlePreviewClick = () => {
-    const content = editorRef.current?.getContent() ?? "";
-    if (content === "") {
-      toast.error("Nothing to preview");
-      return;
-    }
-
-    showPreviewMarkdownDialog(editorRef.current?.getContent() ?? "");
-  };
-
   return (
     <Dropdown>
       <MenuButton
@@ -90,10 +78,6 @@ const MarkdownMenu = (props: Props) => {
           <Icon.CheckSquare className="w-4 h-auto" />
           <span>Checkbox</span>
         </MenuItem>
-        <MenuItem onClick={handlePreviewClick}>
-          <Icon.GanttChartSquare className="w-4 h-auto" />
-          <span>Preview</span>
-        </MenuItem>
         <div className="-mt-0.5 pl-2">
           <Link fontSize={12} href="https://www.usememos.com/docs/getting-started/content-syntax" target="_blank">
             Content syntax

web/src/components/PreviewMarkdownDialog.tsx

-import { IconButton } from "@mui/joy";
-import { useEffect, useState } from "react";
-import { markdownServiceClient } from "@/grpcweb";
-import { Node } from "@/types/proto/api/v1/markdown_service";
-import { generateDialog } from "./Dialog";
-import Icon from "./Icon";
-import MemoContent from "./MemoContent";
-
-interface Props extends DialogProps {
-  content: string;
-}
-
-const PreviewMarkdownDialog: React.FC<Props> = ({ content, destroy }: Props) => {
-  const [nodes, setNodes] = useState<Node[]>([]);
-
-  useEffect(() => {
-    (async () => {
-      try {
-        const { nodes } = await markdownServiceClient.parseMarkdown({ markdown: content });
-        setNodes(nodes);
-      } catch (error) {
-        console.error("Error parsing markdown:", error);
-      }
-    })();
-  }, [content]);
-
-  const handleCloseBtnClick = () => {
-    destroy();
-  };
-
-  return (
-    <>
-      <div className="dialog-header-container">
-        <div className="flex flex-row justify-start items-center">
-          <p className="text-black opacity-80 dark:text-gray-200">Preview</p>
-        </div>
-        <IconButton size="sm" onClick={handleCloseBtnClick}>
-          <Icon.X className="w-5 h-auto" />
-        </IconButton>
-      </div>
-      <div className="flex flex-col justify-start items-start max-w-full w-[32rem]">
-        {nodes.length > 0 ? <MemoContent nodes={nodes} /> : <p className="text-gray-400 dark:text-gray-600">Nothing to preview</p>}
-      </div>
-    </>
-  );
-};
-
-export default function showPreviewMarkdownDialog(content: string): void {
-  generateDialog(
-    {
-      className: "preview-markdown-dialog",
-      dialogName: "preview-markdown-dialog",
-    },
-    PreviewMarkdownDialog,
-    {
-      content,
-    },
-  );
-}